Active-pixel image sensing device with linear mode voltage to current conversion
US6704050B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Apr 23, 1999 |
| Grant date | Mar 9, 2004 |
| Priority date | — |
| Expiry date | Apr 23, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image sensing device comprising active pixels is disclosed, each pixel having a charge accumulation region for collecting charges generated by a photosensitive element such as a photodiode. A linear voltage to current converter, current mirrors, and a differential amplifier generate an output signal and minimize fixed pattern noise and improve the signal to noise ratio. Image quality is improved by reducing pixel blooming and image smearing through an improved method for resetting the pixels with a bias voltage reference which is less than Vdd. Active circuitry and physical device layout reduce the effects of IR voltage drops along the bus lines in a massive pixel array.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.